Remove scipp and ess specifics

[jokasimr]

Recently some ess specifics were re-added to the repo, see scipp/scippneutron#476 and #192 (comment).

We would like to move those specifics to https://github.com/scipp/ess_template if possible, or at least only include them conditionally, if the repo is a scipp- repo or an ess- repo.

One solution would be to make the workflows jinja templates, and make them render the environment variable settings only if the repo is a scipp repo. However, there are some issues with using templates because they are not picked up well by github bots (please correct / clarify this).

[YooSunYoung]

Continuing with this issue, should we remove this dependabot check?
We have lower-bound and latest-released pacakge test so we don't really have to bump scipp asap.

copier_template/template/.github/dependabot.yml

Lines 7 to 13 in a817cfc

	- package-ecosystem: "pip"
	directory: "/requirements"
	schedule:
	interval: "daily"
	allow:
	- dependency-name: "scipp"
	dependency-type: "direct"

I opened a related PR here: scipp/ess_template#10